RecruitingPhase 3NCT07608432

Efficacy, Safety, and Tolerability of Zeleciment Rostudirsen (DYNE-251) Administered Intravenously Every 4 Weeks in Ambulatory Participants With Duchenne Muscular Dystrophy (FORZETTO)

A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study to Investigate the Efficacy, Safety, and Tolerability of DYNE-251 Administered Intravenously in Ambulatory Male Participants 4 to 18 Years of Age With Duchenne Muscular Dystrophy Amenable to Exon-51 Skipping

Sponsor

Dyne Therapeutics

Enrollment

90 participants

Start Date

Jun 1, 2026

Study Type

INTERVENTIONAL

Conditions

Muscular Dystrophy, Duchenne DMD Neuromuscular Diseases (NMD)Muscular Dystrophies Duchenne Muscular Dystrophy (DMD)Muscular Dystrophy in Children Genetic Disease, X-Linked Genetic Disease, Inborn Muscular Dystrophy (DMD)Muscular Dystrophy, Duchenne Type Muscular Dystrophy, Duchenne and Becker Types Muscular Dystrophies (Duchenne, Becker, Myotonic Dystrophy)Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Summary

The purpose of the study is to assess the efficacy, safety, and tolerability of zeleciment rostudirsen (DYNE-251) administered intravenously (IV) every 4 weeks to ambulatory Duchenne muscular dystrophy (DMD) participants, 4 to 18 years of age, with dystrophin mutations amenable to exon 51 skipping.

Eligibility

Sex: MALEMin Age: 4 YearsMax Age: 18 Years

Inclusion Criteria3

Ambulatory male with confirmed diagnosis of DMD and with a mutation in the dystrophin gene characterized by exon deletion amenable to exon 51 skipping .
Rise From Floor (RFF) time must be < 10 seconds for both screening assessments .
Receiving a stable daily or weekend dosage of glucocorticoids for at least 24 weeks prior to randomization with the expectation of maintaining a stable dose during the Placebo-Controlled Period of the study (unless dose adjustment is required by weight change)

Exclusion Criteria7

Receipt of ongoing immunosuppressive therapy (other than glucocorticoids) within 12 weeks prior to randomization
Use of any pharmacologic treatment (other than glucocorticoids) that may have an effect on muscle strength or function within 12 weeks prior to randomization
Any change in prophylaxis/treatment for congestive heart failure (CHF) within 12 weeks prior to randomization
Receipt of eteplirsen within 1 week prior to randomization
Receipt of alternative exon-skipping or dystrophin-modifying therapy or zeleciment rostudirsen within 24 weeks prior to randomization
Receipt of givinostat within 12 weeks prior to randomization
Receipt of gene therapy at any time